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Old 30th October 2010, 09:16 AM   #681
Salas is offline Salas  Greece
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Thanks Salas, I'm testing the concept with a cheap 5842 spud , figure if the Salas HVSS works with that it would work with this, always get ahead of my self though
Have heard before that SSHV marries with a Spud. Is it doing OK on yours? No active reg with some gain and BW must be asked for feeding such an inductive & swinging power load if not heavily cut in internal bandwidth. Then it will lose quality though. There will be things that can't marry. But its nice to try pairings.
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Old 30th October 2010, 09:47 AM   #682
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I should have it put together in a week or so, Quanghao reported success with 6c45pi spud, and I think someone else also, To drive my headphones I only need max 1V (30mW) tested with a 1khz sine wave at about twice my normal listening (this is only 12V on the primary), I'm optimistic but my pre-filtering prior to the HVSS is such that if it doesn't work I can just remove the HVSS and add a 50 uf cap and probably be OK. I'm also going conservative with 4x10k grid stoppers and a cathode stopper.
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Old 30th October 2010, 09:52 AM   #683
Salas is offline Salas  Greece
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Best of luck then.
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Old 30th October 2010, 10:24 AM   #684
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I should have it put together in a week or so, Quanghao reported success with 6c45pi spud, and I think someone else also, To drive my headphones I only need max 1V (30mW) tested with a 1khz sine wave at about twice my normal listening (this is only 12V on the primary), I'm optimistic but my pre-filtering prior to the HVSS is such that if it doesn't work I can just remove the HVSS and add a 50 uf cap and probably be OK. I'm also going conservative with 4x10k grid stoppers and a cathode stopper.
and the good CCS pretty much means you can get away without a top notch PS.
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Old 30th October 2010, 10:40 AM   #685
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and the good CCS pretty much means you can get away without a top notch PS.
Well I'm testing out the Single feed transformer output of the schematic I posted (but with a 5842), thats the issue as far as the HVSS not the CCS stage.
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Old 30th October 2010, 12:17 PM   #686
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sorry regal - i should have read the thread, i though you were parafeeding.
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Old 30th October 2010, 01:28 PM   #687
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sorry regal - i should have read the thread, i though you were parafeeding.

Now I am wondering if parafeed would be an easier matchup to the HVSS.
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Old 5th November 2010, 03:52 AM   #688
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Its simple. If you use a 30mA anode CCS on your audio circuit, the local reg's CCS has to be set higher, so to provide for the audio circuit's consumption plus 20-25mA minimum for its own reg use. So check the voltage drop on your reg's CSS setting resistor, divide it by its value, and know first of all that there is enough current. We should know before going further.
Salas, I found the problem BTW. The SSHV was not controlling the voltage because the IRF 840 got opened for some reason. After I replaced it, everything came back to normal. As you said, I checked the current on anode CCS which is at 9ma and SSHV is at 40ma. Is this the optimal to operate? Now the pre amp is more silent without any speaker rumbling, but I felt the overall gain reduced significantly as well as it lost the liveliness of the music it had with anode chokes. I assume this is because the reduced gain hence any advice to fine tune and increase the gain?
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Old 5th November 2010, 06:01 AM   #689
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A CCS should give as high a gain as possible, may want to check your cathode bypass cap. Or possibly your voltage drop across the CCS is not high enough to keep it from clipping, what is the voltage drop across the CCS (in-out of CCS)?
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Old 5th November 2010, 06:08 AM   #690
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A CCS should give as high a gain as possible, may want to check your cathode bypass cap. Or possibly your voltage drop across the CCS is not high enough to keep it from clipping, what is the voltage drop across the CCS (in-out of CCS)?
Regal, I think the issue is the latter; there is not enough voltage drop. What are the possible reasons for this?

Last edited by coolzero; 5th November 2010 at 06:22 AM.
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